We found replication evidence for GWS loci and a polygenic signal identified in the MVP cohort in an independent sample from UKB. Beyond the consistency of the results obtained, the comparison of MVP and UKB results strongly indicated that, although there is a large difference in combat-exposure between MVP and UKB (41.3% vs. 3.6%), there is still a large genetic overlap between REX phenotypes assessed in these two cohorts. Modest heritability (comparable to that observed for other psychiatric traits, e.g., major depression28) was observed in both samples (MVP h2 = 6.7%; UKB h2 = 4.3%).
